Question

10. Find the cost of sinking a tubewell 210 m deep, having radius 1.5 m at the rate of 3 per cubic metre.
How much will it cost in cementing the inner curved surface at 25 per square metre?
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Answer 1

$=49500$

Step-by-step explanation:

Given ,deep of well=210 m,radius of well=1.5 m,rate of sinking tubewell =3 per cubic meter  and cost of cementing curved surface area of tubewell=25 per square meter

volume of tubewell $=\Pi \times r^{2}\times h$

$=22/7\times 1.5^{2}\times 210$

$=66\times 22.5$

$=1485$ meter square

cost of sinking tube well=volume of tubwell×cost of sinking

$=1485\times 3$

$=4455$

curved surface area of tubell$=2\Pi \times r\times h$

$=2\times 22/7\times 1.5\times 210$

$=1980$ meter square

cost of cementing =curved surface area or tubewell×cost of cementing per square meter

$=1980\times 25$

$=49500$